package map;

import java.util.HashMap;
import java.util.Map;

public class MapDemo2 {
    public static void main(String[] args) {
        Map<String,Integer> map = new HashMap<>();
        map.put("math",100);
        map.put("English",98);
        map.put("history",87);
        map.put("Chinese",75);
        map.put("PE",81);
        System.out.println(map);

        int pe=map.get("PE");
        System.out.println(map);
        int del=map.remove("PE");
        System.out.println(del);
        System.out.println(map);

        System.out.println(map.containsKey("PE"));
        System.out.println(map.isEmpty());
    }
}
